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Objectives This was the first study to systematically landscape and examine China’s nationwide standardized residency training in radiology. Methods In this retrospective cross-sectional study, we used data from the 2019 national survey of the first two cohorts of 3679 radiology residents who completed training in 2017 and 2018 across all 31 provinces in China. A total of 1163 (32%) residents participated in the survey. Multivariable logistic regression was used to examine the implementation frequency of 24 identified training tasks (categorized into six competencies) by region, demographics, and other residency information. Results Among the 1163 respondents, 592 (51%) were trained in the more developed eastern region. Of the 24 identified training tasks, 15 were implemented significantly differently across regions, while the frequency of the most frequently conducted tasks (e.g., CT, MR, and radiograph interpretation and reporting) was consistent. The top 10 tasks all fell into the patient care and medical knowledge competency domains, while other competencies tended to be neglected. We found region and marital status were the most influential factors of training task implementation frequencies. Respondents trained in the northeast and the west were more likely to report, for instance, radiological examination recommendation (OR = 1.91, 95%CI = 1.27–2.88), as “very frequent.” Married respondents were more likely to report first-line night shift as “very frequent” (OR = 1.71, 95%CI = 1.29–2.26). Conclusions Despite the fast-win achievements of developing a national radiology residency training program, there is a gap to train quality and homogeneous radiologists across regions. Future improvement should be more tailored to residents’ personal characteristics and emphasize some “soft” competencies (e.g., communication skills).

Developing effective distributed representations of source code is fundamental yet challenging for many software engineering tasks such as code clone detection, code search, code translation and transformation. However, current code embedding approaches that represent the semantic and syntax of code in a mixed way are less interpretable and the resulting embedding can not be easily generalized across programming languages. In this paper, we propose a disentangled code representation learning approach to separate the semantic from the syntax of source code under a multi-programming-language setting, obtaining better interpretability and generalizability. Specially, we design three losses dedicated to the characteristics of source code to enforce the disentanglement effectively. We conduct comprehensive experiments on a real-world dataset composed of programming exercises implemented by multiple solutions that are semantically identical but grammatically distinguished. The experimental results validate the superiority of our proposed disentangled code representation, compared to several baselines, across three types of downstream tasks, i.e., code clone detection, code translation, and code-to-code search.

Mycoplasma synoviae (MS) infection causes infectious synovitis and arthritis with hyperplasia of synovial cells in the chicken joint. However, its mechanism is unknown. We used primary chicken synovial fibroblast (CSF) as the research object to study the role of MS in the proliferation of MS-infected CSF and determine the mechanisms involved. Using integrated transcriptomic and proteomic analyses of the interaction between CSF and MS, we screened a proliferation-regulated factor, serum amyloid A (SAA), that may regulate proliferation of MS-infected CSF. SAA appears to be associated with MS-induced CSF proliferation. To study the role of SAA in MS-induced CSF proliferation, a eukaryotic expression vector overexpressing SAA and a small interfering RNA (siRNA) targeting Saa were constructed to manipulate the expression of SAA. Cell proliferation and apoptosis were detected via cell counting kit-8 (CCK-8), 5-Ethynyl-2'-deoxyuridine (EdU), or terminal deoxyribonucleotidyl transferase-mediated dUTP nick-dnd labeling (TUNEL) assays, respectively. Western blot analysis was used to examine the protein expression level of SAA, cyclin E1, and cyclin-dependent kinase 2 (CDK2). In vitro, MS significantly promoted the proliferation of CSF and increased the production of SAA. Overexpression of SAA accelerated the proliferative ability of CSF, whereas knockdown of SAA depressed the proliferative ability of CSF. A TUNEL assay indicated that MS did not induce apoptosis. Silencing of SAA suppressed the expression of cyclin E1 and CDK2. These results suggest that MS may upregulate the expression of SAA, accelerate the cell cycle, and promote proliferation of CSF.

Background: Newcastle disease (ND), caused by virulent Newcastle disease virus (NDV), is a huge threat for poultry and birds. LaSota strain of NDV is a common live attenuated vaccine to control ND. In this study, high-throughput RNA sequencing was performed to explore thymus tissue transcriptome change and better manage “vaccine failure” in Chinese Partridge Shank Chickens at 0 h and 48 h post LaSota vaccine injection. Results: 140 long non-coding RNAs (lncRNAs), 8 microRNAs (miRNAs) and 1514 mRNAs were differentially expressed post LaSota NDV vaccine inoculation. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis for vaccine-affected mRNAs and miRNA target genes was conducted. Moreover, 70 innate immune genes (31 up-regulated, 39 down-regulated) inGO, InnateDB and Reactome Pathway databases were found to be differentially expressed. Furthermore, the interaction network of proteins encoded by these dysregulated innate immune genes with known names was established by STRING website. Additionally, expression patterns of some dysregulated lncRNAs, miRNAs and mRNAs were further tested through RT-qPCR assay. Pearson correlation analysis for dysregulated transcripts validated by RT-qPCR assay was also performed. Based on the correlation data, 2 potential competing endogenous RNA (ceRNA) networks (ENSGALT00000060887/gga-miR-6575-5p/paraoxonase 1 (PON1) or MSTRG.188121.10/gga-miR-6631-5p/MMP9) were established. Conclusions: Our data presented many differentially expressed lncRNAs, miRNAs, mRNAs and innate immune genes, and established 2 potential ceRNA networks (lncRNAs/miRNAs/mRNAs) in Chinese Partridge Shank Chickens in response to LaSota vaccine inoculation, which could deepen our understanding on host responses to NDV LaSota vaccine in Chinese Partridge Shank Chickens.

Newcastle disease (ND), caused by virulent Newcastle disease virus (NDV), is a contagious viral disease affecting various birds and poultry worldwide. In this project, differentially expressed (DE) circRNAs, miRNAs and mRNAs were identified by high-throughput RNA sequencing (RNA-Seq) in chicken thymus at 24, 48, 72 or 96 h post LaSota NDV vaccine injection versus pre-inoculation group. The vital terms or pathways enriched by vaccine-influenced genes were tested through KEGG and GO analysis. DE genes implicated in innate immunity were preliminarily screened out through GO, InnateDB and Reactome Pathway databases. The interaction networks of DE innate immune genes were established by STRING website. Considering the high expression of gga-miR-6631-5p across all the four time points, DE circRNAs or mRNAs with the possibility to bind to gga-miR-6631-5p were screened out. Among DE genes that had the probability to interact with gga-miR-6631-5p, 7 genes were found to be related to innate immunity. Furthermore, gga-miR-6631-5p promoted LaSota NDV replication by targeting insulin induced gene 1 (INSIG1) in DF-1 chicken fibroblast cells. Taken together, our data provided the comprehensive information about molecular responses to NDV LaSota vaccine in Chinese Partridge Shank Chickens and elucidated the vital roles of gga-miR-6631-5p/INSIG1 axis in LaSota NDV replication.

Systemic vasculitis involving the breast is a rare clinical condition and may mimic breast cancer or mastitis clinically or radiographically. Here, we report a case of polyarteritis nodosa (PAN) with breast involvement and perform a literature review of published cases of systemic vasculitis affecting the breast to better understand this disorder. We report a case of PAN affecting the right breast in a young woman. A retrospective review was performed by searching Medline, Embase, Web of Science, the Cochrane Library, and Scopus for cases of systemic vasculitis involving the breast written in English up to June 1st, 2018. A 27-year-old woman presented with a painful mass in the right breast was diagnosed as PAN by the biopsy. She was treated with prednisone and methotrexate for 6 months, at which time her condition had stabilized and inflammatory markers had normalized. A total of 66 cases were identified, with granulomatosis with polyangiitis (GPA), giant cell arteritis (GCA), and PAN as the main types. The typical manifestation was mass (79.2%, 53/67) in the breast, and all diagnoses were made by the pathology of the breast biopsy. Glucocorticoid and immunosuppressant were the main therapies, and 74.6% (50/67) patients achieved remission during follow-up. Our case and a literature review of 66 cases of systemic vasculitis involving the breast reveal the importance of tissue biopsy to obtain a definitive diagnosis, because the vasculitis subtype strongly influences prognosis.

The atomic mobilities of Co, Mn, Pt and Re in face-centered cubic (fcc) Co–X ( X = Mn, Pt and Re) alloys have been assessed as a function of temperature and composition by CALculation of PHAse Diagram (CALPHAD) approach. To validate the literature data and provide new experimental data, we prepared two fcc Co–Mn diffusion couples, which were used to determine the composition-dependent inter-diffusivities at 1073 and 1273 K. Based on various kinds of experimental diffusivities available in the literature and the experimental results in this work, the atomic mobilities in fcc Co–X (X = Mn, Pt and Re) alloys were obtained. Comprehensive comparisons between the calculated and measured diffusivities show that most of the experimental data can be well reproduced by the presently obtained atomic mobilities.

Eu-doped Ce:YAG single crystal (SC) was fabricated by the Czochralski method. The crystal structure, optical and photoelectric property of the constructed w-LED was investigated. The XRD and HRTEM results show that YAG crystal structure has little change when Eu3+, Ce3+ are doped. Absorption spectra and photoluminescence spectra show that the Ce,Eu:YAG single crystal can effectively absorb the 460 nm blue light to form a broadband emission center at 530 nm, decay curves of the crystal show that the energy transfer between Ce3+ and Eu3+ is highly suppressed. Compared with commercial Ce:YAG phosphor, Ce,Eu:YAG exhibits better thermal stability.

This study reports the development and optimization of a real-time loop-mediated isothermal amplification (qLAMP) method for rapid detection of Acetobacter aceti strain in red wine samples. Our results showed that the primers and probes designed for 16S rRNA were effective for A. aceti detection. The quantification limit of real-time polymerase chain reaction (qPCR) and qLAMP in pure culture was 2.05 × 101 colony forming units (CFU) mL−1. qLAMP had a sensitivity of 6.88 × 101 CFU mL−1 in artificially contaminated Changyu dry red wine (CDRW) and Changyu red wine (CRW), and 6.88 × 102 CFU mL−1 in artificially contaminated Greatwall dry red wine (GDRW), which was 10 times higher than that of qPCR. In conclusion, this newly developed qLAMP is a reliable, rapid and accurate method for the detection and quantification of A. aceti species in red wine samples. Furthermore, our work provides a standard reference method for the quantitative detection of A. aceti and other acetic acid bacteria during the fermentation and storage of red wine samples.

In modern ion implanters, a plasma flood gun (PFG) is used to neutralize wafer charge during the doping process, preventing the breakdown of floating wafers caused by the space charge accumulation. Typically, there are two kinds of PFGs, namely, dc arc discharge with filament and RF discharge. As a PFG, the filament one has limited lifetime and cannot avoid metallic contamination because of the thermal emitting filament. RF discharge PFG has been developed to solve these problems, including prolonging the source lifetime and avoiding metal pollution. Recently, a 2.45 GHz electron cyclotron resonance (ECR) ion source is also regarded as a potential choice for PFG. However, the dimension of the 2.45 GHz ECR source system including the size of the source itself and its meter’s length RF subsidiary limits its application within an ion implanter. At Peking University, a miniaturized 2.45 GHz permanent magnet electron cyclotron resonance plasma flood gun with a coaxial RF transmission line has been built and tested. The dimensions of the ECR source body are Φ60 mm × Φ88 mm with a Φ30 mm × Φ40 mm plasma chamber. Its RF transmission line consists of a 200 W microwave generator, a 30 cm coaxial line, a 7 cm coaxial-to-waveguide transducer, and a microwave window that also serves as a vacuum seal. In continuous wave experiments, the electron extraction currents can be as high as 8.8 mA at an input RF power of 22 W with argon gas. The gas flow is less than 1.0 SCCM for this test.

Based on 18 bulk diffusion couples, the composition-dependent interdiffusion coefficients in the fcc Co-V-Mo alloys at 1273, 1373 and 1473 K were obtained from the intersection points of the diffusion couples by means of EPMA technique coupled with the Whittle and Green method. With the experimentally determined interdiffusion coefficients and the critically reviewed experimental diffusivities available in the literature, the atomic mobilities of fcc Co-V-Mo alloys were assessed by means of Diffusion Controlled Transformation (DICTRA) software. The quality of the assessed atomic mobilities was confirmed by the comprehensive comparisons between various DICTRA-calculated diffusion behaviors and the experimental ones, including concentration profiles and diffusion paths.

Based on the experimental interdiffusion coefficients from our previous work and the critically reviewed experimental diffusivities available in the literature, the atomic mobilities of Co, Ti and V in fcc Co–Ti–V alloys were assessed by means of DICTRA (DIffusion Controlled TRAnsformation) software. Askill's empirical relations were utilized to assess the self-diffusion coefficients of fcc Ti and fcc V. Comprehensive comparisons between the DICTRA-calculated diffusivities and the experimental data indicate that the presently obtained atomic mobilities can reproduce most of the diffusivities in binary and ternary systems. In addition, a further verification on the obtained atomic mobilities was carried out through comparing the DICTRA-simulated concentration profiles/diffusion paths of the diffusion couples with the corresponding experimental ones. This work contributes to the establishment of a kinetic database for multi-component cemented carbide.

Recipients with a low immunity are under a high risk of infection due to the extensive use of immunosuppressive drugs after renal transplantation. Pulmonary infection after renal transplantation is a prevalent postoperative complication characterized by a wide range of pathogens and high mortality. If the disease cannot be diagnosed in time, then the therapeutic effect will not be effective. This article reviews susceptible factors, high onset time, common pathogens, clinical manifestations, and therapy of pulmonary infection after renal transplantation to provide reference for disease prevention and treatment.

The bolts in the angle steel tower are seriously affected by corrosion and loss. This paper proposes a novel detection system based on YOLO-V3 to avoid the danger of traditional manual detection method for the bolt fault detection of the angle steel tower. A multi-scale convolution module is used to replace the ordinary convolution of original YOLO-V3 so as to obtain the spatial characteristics information of different scales in the image, and enhance the detection accuracy. The experimental results show that mAP of the proposed YOLO-SKIP network is 0.91. Our YOLO-SKIP model has achieved the best detection performance on the defective angle steel tower bolt data.

Superficial solid masses are common conditions in clinical practice, however, some of which can be easily diagnosed and others would be difficult. Although imaging of superficial masses is not always characteristic, it would be helpful to give a definitive diagnosis or narrow a differential diagnosis. Crossing-section imaging can depicture the masses directly, find some pathognomonic signs and demonstrate their relationship with adjacent structures, which can provide decision support for clinician’s reference. Computed tomography (CT) can be used to detect calcifications and bone erosion which could not be seen on radiographs. Magnetic resonance imaging (MRI) is the preferred way for evaluating soft tissue lesions and provides information on hemorrhage, necrosis, edema, cystic and myxoid degeneration, and fibrosis. Other advantages of MRI are its superior soft tissue resolution and any profile imaging, which can aid the assessment of extension and adjacent infiltration. Positron emission tomography (PET)/CT and PET/MRI have been increasingly used in bone and soft tissue sarcomas and provides advantages in the initial tumor staging, tumor grading, therapy assessment, and recurrence detection. Therefore, imaging examination can play an important role in treatment decision making for superficial solid tumors. Here we review the important conditions presenting as superficial mass and show the imaging of typical cases diagnosed in our hospital.

Based on 18 bulk diffusion couples, the composition-dependent interdiffusion coefficients in the FCC Co-rich Co-Ti-V alloys at 1273, 1373 and 1473 K were obtained from the intersection points of the diffusion couples by means of EPMA technique applied to Whittle and Green method. The reliability of the experimental interdiffusivities is validated via thermodynamic constraints. Taking Co as the solvent element, the present results show that when the temperature is from 1273 to 1473 K, the ternary interdiffusion coefficients increases from 10−16 to 10−14 m2/s and the diffusion of Ti is generally faster than V. The ternary main interdiffusion coefficients of $$\tilde{D}_{\text{TiTi}}^{\text{Co}}$$ and $$\tilde{D}_{\text{VV}}^{\text{Co}}$$ at different compositions of Ti and V at 1473 K were compared with the values obtained for boundary binary Co-Ti and Co-V systems in the literature. A composition-dependent decreasing-increasing tendency was found for $$\tilde{D}_{\text{VV}}^{\text{Co}}$$ .

A novel amorphous composite coating was synthesized successfully on low carbon steel by laser cladding FeCrCoNiSiB high-entropy self-fluxed alloy powder. The combination of impact wear and XRD was adopted as a novel method to observe the crystalline phases of the coating. The research focused on the microstructure and high-temperature wear behavior of the two characteristic layers in the fabricated coatings. The amorphous/crystalline layer as the upper layer was composed of amorphous phase and face-centered cubic γ(Fe, Ni) phase, while body-centered cubic (Co, Fe) solid solution phases with carbides and borides precipitates preferred to appear in the bottom layer. The volume fraction of amorphous phase was approximately 49% in the upper layer, which gave birth to a novel wear mechanism and remarkably improve the wear resistance in high-temperature service environment.

Amorphous coating was successfully fabricated on low carbon steel substrates with one-step laser cladding method using CoCrNiSiBFe high-entropy alloy powder. The microstructure and high-temperature wear mechanism of the fabricated coating was investigated. The coating exhibited layered microstructure including the columnar dendrites as the bottom layer and the amorphous-matrix layer with β-Co phase as the minor phase. The content of amorphous phase in the upper surface was up to 85.1%. Different high temperature wear mechanism was exhibited by the two layers leading to a remarkable decrease of wear mass loss and thus a much better wear resistance in the amorphous layer.

In order to support the sustainable development goals, a new single atom fluid is developed where single atom coexistent in solvents mixture. The single atom fluid of Ni/PANI/PyBIG outstandings thermoelectric properties. This fluid simultaneously shows high activity and fluidity due to the intensification effect of single atom. The temperature, pressure and weight fraction of Ni are observed to significantly influence the thermoelectric effect and activity by experiment and DFT simulation. It is found that the Seebeck coefficient and potential are almost increased by 100% as the temperature difference increases from 40 K to 70 K. An increase of weight fraction from 0.1% to 0.4% improves the Seebeck coefficient and the potential by 49.92% and 1.66 times, respectively. An interesting slag phenomenon is also identified. The single atom fluid has wide industrial application value.

The removal of CO2 by lithium silicate is of great significance to alleviate global warming. In order to understand the micro mechanism of the interaction between CO2 and lithium silicate, density functional theory model is developed to explore the effects of B, Al and Ga as dopants and promoters on the CO2 adsorption performance of lithium silicate. Adsorption energy, charge transfer and desorption barrier of CO2 are calculated. It is found that CO2 combines with the lattice oxygen atom on the surface with C atom, and the adsorption energy is −1.91 eV. The doping of B, Al and Ga to Si atom in lithium silicate intensifies the adsorption of CO2 and inhibits the desorption of CO2. Doping of B, Al and Ga to Li atom has the opposite effect. These results provide the interaction mechanism between CO2 and lithium silicate and show the strategy to modify lithium silicate for CO2 capture.

Reactive oxygen species and free radicals play multiple roles in some immune-pathological events. Vitamin E, as a very potent antioxidant, perhaps deceases the potentially negative effects of such oxidative stress to prevent immune-pathological damage to broilers. Therefore, the current study investigated the effects of dietary natural (D-α-tocopherol) and synthetic (DL-α-tocopherol acetate) vitamin E on the growth performance and antioxidant capacity in cyclophosphamide (CY) immunosuppressed broilers. 192 one-day-old male Arbor Acre broilers were randomly distributed into 4 groups: 1) non-CY-challenged control; 2) CY-challenged control; 3) CY-challenged group+20 IU DL-α-tocopherol acetate per kg feed; and 4) CY-challenged group+20 IU D-α-tocopherol per kg feed. The maize-soybean basal diet in the control group contained α-tocopherol (7.12 mg/kg). Broilers were intramuscularly injected with 80 mg/kg body weight of CY or sterile saline at 16, 17, and 18 d of age. CY decreased (P 0.05) the average daily gain and average daily feed intake, but vitamin E did not alter the growth performance of broilers before or after CY injection (P 0.05). The decreased absolute weight of the spleen, thymus and bursa, serum interleukin 2 (IL-2), and interleukin 6 (IL-2) concentrations in CY-treated broilers were alleviated by vitamin E (P 0.05) . The decreased relative weight (g/kg body weight) of the bursa in the CY-treated broilers was increased by natural vitamin E (P 0.05). The CY-induced increases in malondialdehyde (MDA) content and decreases in total antioxidant capacity (T-AOC), glutathione, vitamin C, and α-tocopherol levels, and total superoxide dismutase and glutathione peroxidase activities in both serum and the liver were attenuated by vitamin E (P 0.05). Additionally, natural vitamin E increased α-tocopherol and T-AOC levels and decreased MDA content in the liver of CY-treated broilers (P 0.05) when compared to the synthetic form. In summary, both synthetic and natural vitamin E supplementation improved lymphoid organ weights, serum IL-2 and IL-6 levels, and antioxidant capacity of immunosuppressed broilers induced by CY. Especially, natural vitamin E was superior to the synthetic form and enhanced α-tocopherol and T-AOC levels, reduced MDA concentration in the liver, and alleviated the immune damage of the bursa.

A 2.45 GHz microwave-driven ion source for the generation of multicharged ions has been designed and built at Peking University recently. The magnetic field configuration of this ion source is a minimum-B type with a combination of a hexapole field and an axial mirror field. Argon was selected as the first tested beam generated by this ion source. A 63 µA Ar4+ ion beam at 35 kV extraction voltage was obtained in the pulsed mode (50 Hz/500 µs). Without the hexapole magnetic field, the highest charge state was only Ar2+, and no Ar4+ ion beam was detected. The comparison between the two sets of experimental results with different magnetic configurations has proven the rationality of the production of multicharged ions with this ion source. Both experimental results and discussion will be presented in this paper.

Here, we report the complete genome sequence of Mycoplasma synoviae HN01, a virulent epidemic strain isolated from a sick chicken with synovitis in Henan Province, China. HN01 is the Asian source of an M. synoviae strain that is completely sequenced, genome annotated, and published with relevant data.

In a viable but nonculturable (VBNC) state, bacteria are no longer culturable on standard laboratory media, but still, remain a pathogenic potential and present possible health risks. In this study, we investigated ampicillin's ability, which is commonly used in dairy cattle disease treatment, to induce Cronobacter sakazakii into the VBNC state. After treatment with ampicillin, the counts of culturable cells decreased from 108 CFU/mL to an undetected level 7–30 days post-treatment. Meanwhile, viable cells were still approximately 104–105 cells/mL, and could be resuscitated under appropriate conditions. Fluorescence microscopy showed that VBNC cell maintained apparent cellular integrity, but that the morphology of VBNC cells differed visibly from that of normal cells. Moreover, the respiratory chain activity of VBNC cells were confirmed by flow cytometry (FCM) analysis, suggesting that cells in a VBNC state were physiologically active. Finally, transcriptomics analysis and real-time PCR (qPCR) validation were used to explore the underlying mechanisms of VBNC cell formation. Over-expression of relA, lon, ppx, and ppk in the toxin-antitoxin (TA) trigger system contributed to VBNC cell formation. In the TA trigger system, RelA and exopolyphosphatases/guanosine pentaphosphate phosphohydrolases (PPX/GPPA) synthesize ppGpp, which activates polyphosphate kinase (PPK), the cellular enzyme that accumulates plyphosphate (PolyP). PolyP combines with and stimulates Lon to degrade the antitoxins, thereby activating the toxins that induce a VBNC state. The results of our research will facilitate a better understanding of the survival strategies that bacteria develop to deal with ampicillin pressure and the health risks associated with VBNC Cronobacter sakazakii induced by antibiotics.

At Peking University (PKU), experimental research as well as theoretical study on how to produce high intense H

In order to investigate the damage and collision force of prestressed concrete box bridge subjected to over-height truck collision, refined finite element (FE) models of a simply supported bridge and over-height truck were established, and the accuracy of finite element models was validated. The explicit dynamic FE software, LS-DYNA, was employed to conduct the simulation of over-height truck collision with bridge under 17 cases, which various vehicle impact speeds, vehicle impact masses, over heights of vehicle, thicknesses of carriage, positions of collision and concrete strengths were included in the analysis. The damage of impacted girder under different vehicle velocities was analyzed and the vertical bearing capacity of damaged girder was calculated to investigate its severity of damage. The results indicated that the vertical bearing capacity declined slightly in all cases if the prestressed bars work properly after collision. However, the vertical bearing capacity decreased by 56% once the prestressed bars all failed on the impact side after collision. As the same time, the characteristics of simplified collision force were analyzed and the sensitivity of vital indicators to all load cases were investigated. The results showed that vehicle velocity and carriage thickness exert a non-negligible effect on peak force, and the average force and duration time are mainly influenced by vehicle velocity, vehicle mass, collision height and carriage thickness.

A single σ-phase alloy with a composition of Cr 46 Mn 15.2 Fe 16.3 Co 17 Ni 5.5 (at.%) and a tetragonal lattice structure was produced. The tracer diffusion coefficients of Ni and Fe were measured by secondary electron mass spectroscopy using the highly enriched 64 Ni and 58 Fe natural isotopes. On the homologous temperature scale, Ni and Fe diffuse in the σ-phase faster as compared to the corresponding diffusion rates in the equiatomic and face-centered cubic CoCrFeMnNi alloy. In contrast, on the absolute temperature scale, these elements diffuse roughly at the same rates in both materials. Factors influencing element diffusion and phase stability of the σ-phase compared to the equiatomic alloy are discussed.

Keratin 18 (KRT18) has been suggested to be overexpressed in most types of human tumor, but the expression pattern of KRT18 in colorectal cancer (CRC) remained unknown. In our research, KRT18 protein expression was markedly increased in CRC cancer tissues and cell lines compared with adjacent normal colorectal tissues and normal colonic epithelial cell line, respectively. Meanwhile, we observed high KRT18 expression was associated with advanced clinical stage, deep tumor invasion, lymph node metastasis, distant metastasis, poor differentiation and unfavorable prognosis in CRC patients. Multivariate Cox regression analysis showed high expression of KRT18 was an unfavorable independent predictor for overall survival in CRC patients. The in vitro studies indicated down-regulation of KRT18 expression depressed CRC cell viability, migration and invasion. In conclusion, KRT18 serves as an oncogenic role in CRC progression and may be a therapeutic target for promoting CRC patients’ prognosis.

Cronobacter sakazakii (C. sakazakii), a pathogen that exists in dry and low-moisture environments, such as powder infant formula (PIF), can enter a viable but nonculturable (VBNC) state under harsh conditions, which enables it to escape traditional detection methods and thus poses a potential public health risk. This study aimed at assessing the virulent nature of VBNC C. sakazakii. Our results showed that VBNC C. sakazakii induced intestinal inflammation in neonatal rats. However, the degree of inflammation was significantly lower than that of culturable bacteria due to decreasing endotoxin production, motility, adhesion, and invasion ability in the VBNC state. From the perspective of bacterial translocation, the numbers of C. sakazakii in the blood, liver, and spleen of rats treated with VBNC cells were in the same order of magnitude as those treated with its culturable counterpart and may lead to the same degree of bacteremia. According to the macrophage survival assays, the survival rate of VBNC C. sakazakii within macrophages was 4.7 times higher than that of culturable cells. Based on these findings, we hypothesize that VBNC C. sakazakii evaded the host immune defense system, penetrated the tissue barrier, and translocated to the bloodstream, liver, and spleen through macrophages. Thus, our study reveals that VBNC C. sakazakii could be a potential risk for infants' health.

At Peking University (PKU), a miniaturized 2.45 GHz antenna permanent magnet electron cyclotron resonance (PMECR) ion source , capable of generating a several-mA H + beam, was produced and tested. The dimensions of the plasma chamber were ∅ 30 mm × 40 mm, and the entire size of the ion source (including the extraction system) supply was ∅ 150 mm × 160 mm. A 4.5 mA CW H + beam was extracted at 35 kV with 200 W of microwave power supplied by a compact microwave generator with a coaxial cable . For a better understanding and optimization of the miniaturized ion source, plasma simulations were conducted to research the electromagnetic coupling of the antennas and the generation of ECR plasmas. The experimental and simulation results of the H + , H 2 + , and H 3 + fractions of cylindrical-type and “T”-type antenna microwave ion sources were presented and compared. Based on a series of comparisons between the experimental and simulation results, the impedance of the miniaturized antenna ECR ion source plasma and the real pressure in the plasma chamber were accurately calculated. An optimized microwave coupling system was designed for the new miniaturized antenna ECR ion source. From the plasma simulation results, the transmission efficiency of microwaves increased from 32% to 89% (coupled to plasma), 15 mA H + @ 150 W can be expected in the future.

Carbon dioxide capture significantly helps achieve the carbon neutral goal. Chemical absorption of CO by the solvent meets the bottleneck of the high energy consumption. An advanced solvent of CuH/PANI/TEMPO has been developed to reduce the energy consumption. The metal hydride CuH decomposes into the Cu atom to intensify the thermoelectric effect between PANI and TEMPO. The strong thermoelectric effect has the potential to enhance the CO desorption. DFT model and mass and energy transfer model in the nano-scale are developed accurately to quantify the system of CO and CuH/PANI/TEMPO. The CO fraction, electron density and velocity in the nano-domain are studied. It is found that the symmetrical electron density zone is produced. The mass transfer coefficient is improved by 2.15 times with 4.65 × 10 m/s and the energy consumption is reduced to 1.02GJ/tCO. The thermoelectric conversion accounts for 31.4%–43.5% of the overall energy transfer.

Cronobacter sakazakii (C. sakazakii) in viable but nonculturable (VBNC) state might evade traditional culture detection, and pose a serious threat to food safety. The objective of this study was to establish an improved propidium monoazide (PMAxx), combined with a single intact cell droplet digital PCR (SIC ddPCR) method for rapid and absolute quantification of VBNC C. sakazakii and apply it to the detection of several infant foods. In this study, we optimized the detection conditions for C. sakazakii, and determined the optimal PMAxx final concentration (8 μM), light exposure times (10 min), annealing temperature (58 °C) and elongation time (1 min). In addition, PMAxx-SIC ddPCR demonstrated a higher detection sensitivity and accuracy relative to real-time PCR (qPCR), with 23 CFU/mL in pure culture. Furthermore, PMAxx-SIC ddPCR was used to detect VBNC C. sakazakii in the actual infant food samples. A total of 240 samples were analyzed, out of which 6 samples turned out to be positive by the traditional culture method, whereas 11 samples were found as positive by PMAxx-SIC ddPCR. These results demonstrate that the presence of VBNC may cause the conventional culture-based method to underestimate the size of microbial population.

This article presents a new method for structure assessment based on weigh-in-motion data and simulation analysis. The focus is particularly on the simply supported hollow slab bridges and extra-he...

The initial grains of H62 brass alloy are refined after continuous extrusion, and the dynamic recrystallization occurs in the forming process. Mastering the driving forces of microstructure evolution are the key for exploring the deformation characteristics of two-phase H62 brass during continuous extrusion. The optical microscope (OM) and the transmission electron microscope (TEM) were used to observe the whole regions of H62 brass. The results show that the microstructure in groove rolling region is flatter than that in raw material. The dislocations and twins are found in α phases, and β phases are broken and distributed in the boundary of α phases in the adhesion region. The dynamic recrystallization is found in the right angle deformation region, and more dislocations and twins in α phases and more fine grains of β phases are found in this region than ones in the adhesion region. For extrusion deformation region, more dislocations in α phases and β phases, and more twins in α phases in lower part than ones in the upper part for this region, which indicates the key microstructure evolution concentrates on the lower part for extrusion deformation region. The results are benefit to guide obtaining the product with excellent properties.

Nitrogen ions with different energy of 30 keV and 50 keV and dose of 5 × 1016, 5 × 1017 and 1 × 1018 cm− 2 were implanted into the surface of AISI 420 martensitic stainless steel. The micro topography, roughness, friction coefficient, wear loss, hardness, as well as the chemical composition were investigated. Mounds and craters were found on the ion implanted surfaces, indicating increases in the roughness. However, very little changes in friction coefficient were detected after implantation. Nitrogen ions implantation on AISI 420 significantly improved the nanohardness, and the value of 16.2 GPa at the depth of 17.3 nm was about 2.3 times as hard as the untreated samples at the same depth when the implant energy and dose were 50 keV and 5 × 1016 cm− 2, respectively. The wear loss of the implanted samples was less than that of untreated ones, and an optional dose of 5 × 1017 cm− 2 could be used for the wear resistance improvement. XPS results demonstrated that chromium nitrides were produced during ion implantation, which possibly contributes to the improvements of the hardness and wear resistance. The N 1s core spectra showed that nitrogen oxides was found in the samples with higher implantation dose, which had counteraction for the improvements of the hardness.

Introduction Quadrilateral space syndrome (QSS) is a peripheral nerve entrapment disease, which can be misdiagnosed in clinic. In the past, QSS was mainly diagnosed by clinical symptoms combined with magnetic resonance imaging (MRI), electromyography (EMG), and arterial angiography. There are few reports on the diagnosis of QSS by musculoskeletal ultrasound (MSKUS) combined with clinical symptoms. Patient concerns A middle-aged female patient had posterolateral pain and numbness in her right shoulder for 2 months. Diagnoses At first, she was diagnosed as suprascapular nerve entrapment, while EMG of suprascapular nerve and axillary nerve indicated that nerve conduction was normal. Then, MRI was performed, showing the shoulder had no abnormalities, and EMG and arterial angiography of upper limb showed no abnormalities too. Finally, she was diagnosed as QSS according to MSKUS and lidocaine block test. Interventions Two sealing treatments of axillary nerve block in quadrilateral space under the guidance of MSKUS were performed. Outcomes After 2 treatments, the pain and numbness in her shoulder disappeared, and her shoulder could move normally. There was no recurrence after 3 months of follow-up. Conclusion MSKUS is an effective method to diagnose QSS. It is fast, convenient and inexpensive, and is worth popularizing in clinic.

A single Cr-rich σ-phase alloy with a composition of Co17Cr46Fe16.3Mn15.2Ni5.5 (at.%) and a tetragonal lattice structure was produced. The tracer diffusion coefficients of Ni and Fe were measured by secondary ion mass spectroscopy using the highly enriched 64Ni and 58Fe natural isotopes. On the homologous temperature scale, Ni and Fe diffuse in the σ phase faster as compared to the corresponding diffusion rates in the equiatomic and face-centered cubic CoCrFeMnNi alloy. In contrast, on the absolute temperature scale, these elements diffuse roughly at the same rates in both materials. Factors influencing element diffusion and phase stability of the σ phase compared to the equiatomic alloy are discussed.

The 2.45 GHz electron cyclotron resonance ion source (ECRIS) is recognized as one of the most efficient devices for the production of high intensity H+, H2+ and H3+ beams. To elucidate the mechanism of electron cyclotron heated (ECH) hydrogen plasma, a global model based on the energy and particle balance equations is developed at Peking University (PKU). This model is applied to a permanent magnet ECRIS named PMECR II at PKU to study the dependences of the H+, H2+, and H3+ ion fractions of the extracted beam on the gas pressure, microwave power, wall material and chamber diameter. The calculated results obtained with the global model are in good agreement with the experimental results. Moreover, a more compact 2.45 GHz ECR ion source is designed and operated under the guidance of the model for the generation of H+, H2+ and H3+ ion dominated beams. Beams with H+, H2+ and H3+ ion fractions greater than 80% were produced under optimized gas pressure and microwave power with this new ECR source.